Go Back   IceInSpace > Equipment > Astrophotography and Imaging Equipment and Discussions

Reply
 
Thread Tools Rate Thread
  #1  
Old 06-10-2017, 04:51 PM
Lognic04's Avatar
Lognic04 (Logan)
Registered User

Lognic04 is offline
 
Join Date: Mar 2016
Location: Melbourne, VIC
Posts: 889
Combining data with different levels of light pollution?

Hi all,
Have been thinking about combining data from different levels of light pollution recently, because it's hard to get enough exposures in one night at a dark site to remove noise. I'm thinking that the data with more light pollution will kill off the fainter bits of the image. Would this actually work well?
Reply With Quote
  #2  
Old 06-10-2017, 05:41 PM
billdan's Avatar
billdan (Bill)
Registered User

billdan is offline
 
Join Date: Mar 2012
Location: Narangba, SE QLD
Posts: 1,551
In those situations it may be better to stack each night separately and then stack each stack as a median stack, as each stack is already calibrated you won't need to use darks or flats again.

EDIT: That's what I do with data that has been meridian flipped, stack each separately and then flip one of the stacks and then stack the two stacks.

Last edited by billdan; 06-10-2017 at 05:52 PM.
Reply With Quote
  #3  
Old 06-10-2017, 06:10 PM
Atmos's Avatar
Atmos (Colin)
Ultimate Noob

Atmos is offline
 
Join Date: Aug 2011
Location: Melbourne
Posts: 6,980
It depends on how much light pollution you’re dealing with and how dark your dark skies are

If I was to try it on faint bits from my dark site and light polluted home, 1 hour of dark sky would probably equal around 6-10 hours of light polluted skies. This is in LRGB and not narrowband btw.
Reply With Quote
  #4  
Old 06-10-2017, 06:43 PM
gregbradley's Avatar
gregbradley
Registered User

gregbradley is offline
 
Join Date: Feb 2006
Location: Sydney
Posts: 17,877
I kind of doubt it will work. You will just degrade the good dark site data.

I think you would be better off imaging just the brighter objects so you can get enough data to put together an image.

Also keep a library of your data so next year when you image that object again you can add the year's before data to the recently collected data.

Also the need to collect enough data quickly is why the trend is for largish aperture fast scopes with quite sensitive cameras and not oversampling too much.

Greg.
Reply With Quote
  #5  
Old 06-10-2017, 08:05 PM
Alexborek (Alexandre)
Registered User

Alexborek is offline
 
Join Date: Sep 2017
Location: Sydney
Posts: 5
You can try to do a photometric callibration and extract the background brightness (and gradient) for further corrections. Not easy but works!
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 05:31 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Advertisement
Testar
Advertisement
Bintel
Advertisement